This invention relates to an engine for producing a supply of hydraulic fluid under a high pressure for driving a hydraulic motor or like hydraulic driven device. More particularly, this invention relates to an internal combustion engine which drives a piston for pressurizing hydraulic fluid.
An aim of the present invention is to provide a new and improved hydraulic engine of efficient construction having a compression ignition power source for pressurizing hydraulic fluid thereby providing an energy source for various hydraulically actuated devices. The hydraulic engine has a linear configuration and employs a free floating composite piston member which reciprocates to pressurize hydraulic fluid. The pressurized fuel employed for driving the piston is pressurized by means of an intensifier pump which is driven by the piston and coordinated with the movement of the reciprocating piston. A hydraulically actuated starting means is employed to start the operation of the engine. The timing and operation of the engine is governed by a hydraulically actuable distributor valve.
Briefly stated, the invention in a preferred form is an internal combustion hydraulic engine having a cylinder which receives pressurized fuel for combustion at one end and receives hydraulic fluid for pressurization at a second end. The cylinder interiorly forms three concentric axial bores having from the one end progressive constant reduced diameters. A piston comprising three interconnected pistons is reciprocatable in the cylinder bores to form a combustion chamber, a scavenger pressure chamber communicatable with the combustion chamber, a piston return chamber and a work chamber. A low pressure conduit selectively connects the return chamber to a reservoir tank which provides a source of hydraulic fluid under a low pressure. A high pressure conduit selectively connects the return chamber to an accumulator tank which provides a source of hydraulic fluid under a high pressure. A distributor valve is interposed in the low pressure conduit and the high pressure conduit and is selectively positionable at a first position to allow fluid communication for releasing pressure from the return chamber. The distributor valve is selectively positionable at a second position to allow fluid communication for pressurizing the return chamber to force the piston toward the first end of the cylinder to pressurize the combustion chamber. A pair of starting valves in fluid communication with the distributor valve are employed to selectively move the distributor valve to the first and second positions for starting the engine. In a preferred embodiment, the distributor valve is a spool valve which is positionable in response to hydraulic pressure, and the starting valves are axially depressable spring biased spool valves. An intensifier pump is employed to pressurize fuel for delivery to an injector nozzle for injection into the combustion chamber. The intensifer pump is hydraulically driven by the reciprocation of the piston and comprises a spring biased plunger which is reciprocatable in a pump chamber in coordination with the reciprocating piston.
An object of the invention is to provide a new and improved internal combustion hydraulic engine.
Another object of the invention is to provide new and improved means for starting the operation of a linear configured, compression/ignition powered hydraulic engine.
A further object of the invention is to provide a new and improved hydraulic engine of efficient construction wherein pressurized fuel employed to power the engine is pressurized by means of hydraulic power generated by the engine.
Other objects and advantages of the invention will become apparent from the drawing and the specification.